Production optimization and application of medium chain carboxylic acid

doi:10.16085/j.issn.1000-6613.2024-2075

Abstract

Abstract:

With the rapid development of animal husbandry, the environmental pressure generated by organic waste is increasing day by day. Therefore, developing efficient organic waste treatment technologies is particularly crucial. Among them, the use of microbial carbon chain extension technology to convert organic waste into medium chain carboxylic acids has received attention due to its high energy density and diverse application prospects, which can be used in fields such as biofuels, feed additives, pharmaceuticals, food, and cosmetics. The review first outlines the current development status of animal husbandry, and then delves into the application of anaerobic digestion technology in waste treatment, with a particular focus on the process of producing medium chain carboxylic acids through anaerobic technology. It analyzes the factors that affect anaerobic digestion efficiency and medium chain carboxylic acid production, such as pH, temperature, hydraulic retention time, hydrogen partial pressure, and carbon-to-nitrogen ratio. In addition, the purification methods of caproic acid and its various uses in agriculture, such as antibacterial agents, plant growth promoters, and organic fertilizers, are discussed in detail, emphasizing their potential benefits in improving crop yield and quality, and reducing diseases. Finally, the agricultural applications of biogas slurry and sludge generated during anaerobic digestion, such as organic fertilizers and soil amendments, are also mentioned, and future research directions are proposed to optimize anaerobic digestion technology, improve the production efficiency of medium chain carboxylic acids, and reduce costs, further exploring their potential applications in agriculture and resource utilization.

Key words: medium chain carboxylic acid, anaerobic, optimization, reaction

摘要：

随着畜牧业的快速发展，畜禽粪便产生的环境压力日益增大。因此，开发高效的有机废弃物处理技术显得尤为关键。其中，利用微生物碳链延长技术将有机废弃物转化为中链羧酸又因其高能量密度和多元化的应用前景而受到重视，可用于生物燃料、饲料添加剂、医药、食品和化妆品等领域。本文初步概述了当前畜牧业的发展态势，继而深入剖析了厌氧消化技术在有机废弃物处理中的应用，特别关注了通过厌氧技术生产中链羧酸的工艺。分析了影响厌氧消化效率和中链羧酸产量的因素，如pH、温度、水力停留时间、氢分压和碳氮比等。此外，重点讨论了中链羧酸的提纯方法及其多种用途，如动物饲料、食品添加剂、医疗药物、燃料等；农业领域如抗菌剂、植物生长促进剂和有机肥料等，强调了其在提升作物产量和质量、减少病害方面的潜在效益。最后，阐述了厌氧消化过程中产生的沼液和沼渣的农业应用，如有机肥料和土壤改良剂，并提出了未来研究的方向，以优化厌氧消化技术、提高中链羧酸的生产效率以及降低生产成本，进一步探索其在农业和资源化利用中的应用潜力。

关键词: 中链羧酸, 厌氧, 优化, 反应

CLC Number:

TQ921

ZHANG Haozhen, LIU Yang, YE Xiaomei, ZHANG Hongyu, ZHAO Keke, ZHU Fei, SUN Xiaochuan, XI Yonglan. Production optimization and application of medium chain carboxylic acid[J]. Chemical Industry and Engineering Progress, 2025, 44(12): 7214-7225.

张浩祯, 刘洋, 叶小梅, 张鸿宇, 赵苛苛, 朱飞, 孙小川, 奚永兰. 中链羧酸生产的优化与应用[J]. 化工进展, 2025, 44(12): 7214-7225.

Figures/Tables 6

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提纯技术	萃取产率	萃取效率/%	参考文献
内联膜电解系统	610g/(m²·d)	53.9±0.34	[36]
电渗析系统	(260±38)g/(m²·d)	15±3.1	[37]
油凝胶提取	8.59g/(L·d)	87.39±0.96	[38]
渗透法结合膜电解技术	(1.7±0.6)g/(L·d)	73	[39]
颗粒化发酵高速链延伸	12.3g/(L·d)	44.4	[40]
在线萃取系统	(143.4±14.8)mmol/(L·d)	55	[41]

提纯技术	萃取产率	萃取效率/%	参考文献
内联膜电解系统	610g/(m²·d)	53.9±0.34	[36]
电渗析系统	(260±38)g/(m²·d)	15±3.1	[37]
油凝胶提取	8.59g/(L·d)	87.39±0.96	[38]
渗透法结合膜电解技术	(1.7±0.6)g/(L·d)	73	[39]
颗粒化发酵高速链延伸	12.3g/(L·d)	44.4	[40]
在线萃取系统	(143.4±14.8)mmol/(L·d)	55	[41]

底物	电子供体	温度/℃	pH	最大产率/产量（己酸）	参考文献
污泥	乙醇	40	5.4	9.80g/L	[71]
污泥	乙醇	37	7.1	(5.28±0.18)g/L	[72]
污泥	乙醇	35	6.9	6.268g/L	[73]
污泥	乙醇	37	7	66.97mmol/L	[74]
污泥	乙醇	30	6.2	3.115g/(L·d)	[29]
猪粪	乳酸	30	6	7.733g/L	[75]
猪粪	乳酸	50	6	1.29g/(L·d)	[70]
猪粪	乙醇	35	6.5	27.6g/L	[76]
食物垃圾	乙醇	30	7.5	33.108g/L	[77]
食物垃圾	乙醇	30	5.5	4.667g/(L·d)	[78]
餐厨垃圾	乳酸、乙醇	35	7	18.443g/L	[79]
餐厨垃圾	乙醇	35	6.75	(0.707±0.0395)g/g	[80]

底物	电子供体	温度/℃	pH	最大产率/产量（己酸）	参考文献
污泥	乙醇	40	5.4	9.80g/L	[71]
污泥	乙醇	37	7.1	(5.28±0.18)g/L	[72]
污泥	乙醇	35	6.9	6.268g/L	[73]
污泥	乙醇	37	7	66.97mmol/L	[74]
污泥	乙醇	30	6.2	3.115g/(L·d)	[29]
猪粪	乳酸	30	6	7.733g/L	[75]
猪粪	乳酸	50	6	1.29g/(L·d)	[70]
猪粪	乙醇	35	6.5	27.6g/L	[76]
食物垃圾	乙醇	30	7.5	33.108g/L	[77]
食物垃圾	乙醇	30	5.5	4.667g/(L·d)	[78]
餐厨垃圾	乳酸、乙醇	35	7	18.443g/L	[79]
餐厨垃圾	乙醇	35	6.75	(0.707±0.0395)g/g	[80]